T\u1eeb kh\u00f3a t\u00ecm ki\u1ebfm: H\u00e3y Tr\u1ea3 L\u1eddi Em T\u1ea1i Sao? \u2013 T\u1eadp 10 – Arkady Leokum<\/p>\n\n\n\n
H\u1ea7u h\u1ebft lo\u00e0i d\u01a1i ch\u1ec9 ho\u1ea1t \u0111\u1ed9ng ban \u0111\u00eam. Ch\u00fang bay trong \u0111\u00eam \u0111\u1ec3 ki\u1ebfm th\u1ee9c \u0103n. Bao n\u0103m qua, ng\u01b0\u1eddi ta ng- hi\u00ean c\u1ee9u v\u1ec1 d\u01a1i v\u00e0 th\u1eafc m\u1eafc kh\u00f4ng bi\u1ebft l\u00e0m sao ch\u00fang l\u1ea1i nh\u00ecn th\u1ea5y \u0111\u01b0\u1ee3c trong \u0111\u00eam t\u1ed1i. L\u00e0m c\u00e1ch n\u00e0o m\u00e0 m\u1ed9t con d\u01a1i \u1edf n\u01a1i kh\u00f4ng c\u00f3 \u00e1nh s\u00e1ng, v\u1eeba bay v\u1eeba b\u1eaft \u0111\u01b0\u1ee3c nh\u1eefng c\u00f4n tr\u00f9ng c\u00f3 c\u00e1nh?<\/p>\n\n\n\n
Nhi\u1ec1u ng\u01b0\u1eddi th\u01b0\u1eddng ngh\u0129 r\u1eb1ng lo\u00e0i d\u01a1i c\u00f3 th\u1ecb l\u1ef1c tuy\u1ec7t h\u1ea3o l\u1ea1 k\u1ef3: ch\u00fang c\u00f3 th\u1ec3 th\u1ea5y \u0111\u01b0\u1ee3c trong \u00e1nh s\u00e1ng h\u1ebft s\u1ee9c m\u1edd nh\u1ea1t m\u00e0 m\u1eaft ng\u01b0\u1eddi kh\u00f4ng th\u1ec3 \u0111i\u1ec1u ti\u1ebft. Nh\u1eefng nh\u00e0 khoa h\u1ecdc ng\u00e0y nay \u0111\u00e3 bi\u1ebft r\u1eb1ng m\u1ed9t con d\u01a1i c\u00f3 kh\u1ea3 n\u0103ng bay l\u01b0\u1ee3n, kh\u00f4ng ph\u1ea3i ch\u1ec9 nh\u1edd \u0111\u00f4i m\u1eaft m\u00e0 c\u00f2n nh\u1edd hai tai v\u00e0 nh\u1eefng c\u01a1 quan ph\u00e1t \u00e2m.<\/p>\n\n\n\n
Tr\u1edf l\u1ea1i nh\u1eefng n\u0103m 1780, m\u1ed9t nh\u00e0 \u0111\u1ed9ng v\u1eadt h\u1ecdc ng\u01b0\u1eddi \u00dd t\u00ean l\u00e0 Spallanzani \u0111\u00e3 l\u00e0m m\u1ed9t th\u00ed nghi\u1ec7m. \u00d4ng b\u1ecbt m\u1eaft v\u00e0i con d\u01a1i v\u00e0 th\u1ea3 ch\u00fang trong m\u1ed9t c\u0103n ph\u00f2ng c\u1ea3 m\u1ed9t m\u1ea1ng ch\u1ec9 \u0111an ch\u00e9o nhau. Nh\u1eefng con d\u01a1i \u1ea5y \u0111\u00e3 bay qua m\u00ea cung m\u00e0 ch\u1eb3ng \u0111\u1ee5ng ph\u1ea3i m\u1ed9t s\u1ee3i ch\u1ec9 n\u00e0o. Nh\u00e0 khoa h\u1ecdc c\u1ea3m nh\u1eadn r\u1eb1ng d\u01a1i \u0111\u00e3 d\u00f9ng tai h\u01a1n l\u00e0 m\u1eaft \u0111\u1ec3 t\u00ecm \u0111\u01b0\u1eddng trong \u0111\u00eam t\u1ed1i.<\/p>\n\n\n\n
N\u0103m 1920, m\u1ed9t nh\u00e0 khoa h\u1ecdc kh\u00e1c g\u1ee3i \u00fd l\u00e0 lo\u00e0i d\u01a1i \u0111\u00e3 d\u00f9ng nh\u1eefng t\u00edn hi\u1ec7u ngo\u00e0i t\u1ea7m nghe c\u1ee7a con ng\u01b0\u1eddi. Nh\u1eefng \u00e2m thanh n\u00e0y g\u1ecdi l\u00e0 si\u00eau \u00e2m. N\u0103m 1941, hai nh\u00e0 khoa h\u1ecdc kh\u00e1c quy\u1ebft \u0111\u1ecbnh d\u00f9ng m\u1ed9t thi\u1ebft b\u1ecb \u0111i\u1ec7n t\u1eed t\u1ed1i t\u00e2n \u0111\u1ec3 c\u00f3 th\u1ec3 d\u00f2 t\u00ecm nh\u1eefng si\u00eau \u00e2m trong m\u1ed9t th\u00ed nghi\u1ec7m v\u1edbi lo\u00e0i d\u01a1i.<\/p>\n\n\n\n
M\u00e1y \u1ea5y ch\u1ee9ng minh r\u1eb1ng d\u01a1i ph\u00e1t ra nh\u1eefng ti\u1ebfng k\u00eau c\u00f3 \u00e2m thanh cao v\u00fat v\u00e0 ch\u00fang kh\u00f4ng ng\u1eebng ph\u00e1t ra ti\u1ebfng k\u00eau khi bay qua m\u1ed9t m\u00ea cung to\u00e0n d\u00e2y \u0111i\u1ec7n ch\u1eb1ng ch\u1ecbt trong \u0111\u00eam t\u1ed1i. Khi ng\u01b0\u1eddi ta d\u00e1n mi\u1ec7ng d\u01a1i l\u1ea1i, nh\u1eefng con v\u1eadt n\u00e0y b\u1ecb thi\u1ec7t h\u1ea1i n\u1eb7ng.<\/p>\n\n\n\n
D\u01a1i ph\u00e1t ra nh\u1eefng t\u00edn hi\u1ec7u – \u0111\u00f3 l\u00e0 nh\u1eefng ti\u1ebfng k\u00eau c\u00f3 \u00e2m thanh cao v\u00fat, g\u1eb7p v\u1eadt g\u00ec tr\u00ean \u0111\u01b0\u1eddng bay \u00e2m thanh n\u00e0y \u0111\u1ec1u d\u1ed9i tr\u1edf l\u1ea1i. M\u1ed9t \u00e2m thanh d\u1ed9i tr\u1edf l\u1ea1i hay ph\u1ea3n h\u1ed3i g\u1ecdi l\u00e0 ti\u1ebfng d\u1ed9i. D\u01a1i s\u1eed d\u1ee5ng ti\u1ebfng d\u1ed9i \u0111\u1ec3 \u0111\u1ecbnh v\u1ecb c\u00e1c v\u1eadt trong \u0111\u00eam t\u1ed1i.<\/p>\n\n\n\n
C\u00e1c nh\u00e0 khoa h\u1ecdc g\u1ecdi s\u1ef1 \u0111\u1ecbnh v\u1ecb ti\u1ebfng d\u1ed9i n\u00e0y c\u0169ng gi\u1ed1ng nh\u01b0 h\u1ec7 th\u1ed1ng ra\u0111a.<\/p>\n","protected":false},"excerpt":{"rendered":"
T\u1eeb kh\u00f3a t\u00ecm ki\u1ebfm: H\u00e3y Tr\u1ea3 L\u1eddi Em T\u1ea1i Sao? \u2013 T\u1eadp 10 – Arkady Leokum H\u1ea7u h\u1ebft lo\u00e0i d\u01a1i ch\u1ec9 ho\u1ea1t \u0111\u1ed9ng ban \u0111\u00eam. Ch\u00fang bay trong \u0111\u00eam \u0111\u1ec3 ki\u1ebfm th\u1ee9c \u0103n. Bao n\u0103m qua, ng\u01b0\u1eddi ta ng- hi\u00ean c\u1ee9u v\u1ec1 d\u01a1i v\u00e0 th\u1eafc m\u1eafc kh\u00f4ng bi\u1ebft l\u00e0m sao ch\u00fang l\u1ea1i nh\u00ecn th\u1ea5y \u0111\u01b0\u1ee3c […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[15],"tags":[],"class_list":["post-15674","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/15674","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=15674"}],"version-history":[{"count":1,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/15674\/revisions"}],"predecessor-version":[{"id":15675,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/15674\/revisions\/15675"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=15674"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=15674"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=15674"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}